#pragma once

#include "all.qh"

#ifdef GAMEQC
CLASS(Inventory, Object)
    /** Stores counts of items, the id being the index */
    ATTRIBARRAY(Inventory, inv_items, int, REGISTRY_MAX(Items));
ENDCLASS(Inventory)

/** Player inventory */
.Inventory inventory;
/** Player inventory storage (holds previous state) */
.Inventory inventory_store;

REGISTER_NET_LINKED(ENT_CLIENT_INVENTORY)

const int Inventory_groups_minor = 8; // must be a multiple of 8 (one byte) to optimize bandwidth usage
const int Inventory_groups_major = 4; // must be >= ceil(REGISTRY_COUNT(Items) / Inventory_groups_minor)
#endif

// no need to perform these checks on both server and client
#ifdef CSQC
STATIC_INIT(Inventory)
{
	if (Inventory_groups_minor / 8 != floor(Inventory_groups_minor / 8))
		error("Inventory_groups_minor is not a multiple of 8.");
	int min_major_value = ceil(REGISTRY_COUNT(Items) / Inventory_groups_minor);
	if (Inventory_groups_major < min_major_value)
		error(sprintf("Inventory_groups_major can not be < %d.", min_major_value));
}
#endif

#ifdef SVQC
#define G_MAJOR(id) (floor((id) / Inventory_groups_minor))
#define G_MINOR(id) ((id) % Inventory_groups_minor)
#endif

#ifdef CSQC
Inventory g_inventory;
void Inventory_remove(entity this)
{
    if(g_inventory == this)
        g_inventory = NULL;
}

NET_HANDLE(ENT_CLIENT_INVENTORY, bool isnew)
{
    make_pure(this);
    g_inventory = this;
    this.entremove = Inventory_remove;
    const int majorBits = Readbits(Inventory_groups_major);
    for (int i = 0; i < Inventory_groups_major; ++i) {
        if (!(majorBits & BIT(i))) {
            continue;
        }
        const int minorBits = Readbits(Inventory_groups_minor);
        for (int j = 0; j < Inventory_groups_minor; ++j) {
            if (!(minorBits & BIT(j))) {
                continue;
            }
            const GameItem it = REGISTRY_GET(Items, Inventory_groups_minor * i + j);
            .int fld = inv_items[it.m_id];
            int prev = this.(fld);
            int next = this.(fld) = ReadByte();
            LOG_DEBUGF("%s: %.0f -> %.0f", it.m_name, prev, next);
        }
    }
    return true;
}
#endif

#ifdef SVQC
int minorBitsArr[Inventory_groups_major];
void Inventory_Write(Inventory data, Inventory store)
{
    if (!data) {
        WriteShort(MSG_ENTITY, 0);
        return;
    }
    TC(Inventory, data);

	for (int i = 0; i < Inventory_groups_major; ++i)
		minorBitsArr[i] = 0;

    int majorBits = 0;
    FOREACH(Items, true, {
        .int fld = inv_items[it.m_id];
        const bool changed = store.(fld) != data.(fld);
        store.(fld) = data.(fld);
        if (changed) {
			int maj = G_MAJOR(it.m_id);
			majorBits = BITSET(majorBits, BIT(maj), true);
			minorBitsArr[maj] = BITSET(minorBitsArr[maj], BIT(G_MINOR(it.m_id)), true);
        }
    });

	Writebits(MSG_ENTITY, majorBits, Inventory_groups_major);
	for (int i = 0; i < Inventory_groups_major; ++i)
	{
		if (!(majorBits & BIT(i)))
			continue;

		const int minorBits = minorBitsArr[i];
		Writebits(MSG_ENTITY, minorBits, Inventory_groups_minor);
		for (int j = 0; j < Inventory_groups_minor; ++j)
		{
			if (!(minorBits & BIT(j)))
				continue;

			const entity it = REGISTRY_GET(Items, Inventory_groups_minor * i + j);
			WriteByte(MSG_ENTITY, data.inv_items[it.m_id]);
		}
	}
}
#endif

#undef G_MAJOR
#undef G_MINOR

#ifdef SVQC
bool Inventory_Send(Inventory this, Client to, int sf)
{
    TC(Inventory, this);
    WriteHeader(MSG_ENTITY, ENT_CLIENT_INVENTORY);
    TC(PlayerState, this.owner);
    Inventory_Write(this, to.inventory_store);
    return true;
}

bool Inventory_customize(entity this, entity client)
{
    // sends to spectators too!
    return (PS(client) && PS(client).inventory == this);
}

void Inventory_new(PlayerState this)
{
    Inventory inv = NEW(Inventory);
    setcefc(inv, Inventory_customize);
	this.inventory = inv;
	inv.owner = this;
	Net_LinkEntity(inv, false, 0, Inventory_Send);
}
void Inventory_delete(entity e) { delete(e.inventory); }
void Inventory_update(entity e) { e.inventory.SendFlags = 0xFFFFFF; }

void Inventory_clear(entity store)
{
    // NOTE: you will need to perform Inventory_update after this to update the storage entity
    // (unless store is the storage entity)
    FOREACH(Items, true, {
        .int fld = inv_items[it.m_id];
        store.(fld) = 0;
    });
}

void InventoryStorage_attach(entity e) { e.inventory_store = NEW(Inventory); e.inventory_store.drawonlytoclient = e; }
void InventoryStorage_delete(entity e) { delete(e.inventory_store); }
#endif